Propulsion device having at least one flexible blade

ABSTRACT

A propulsion device is disclosed which uses at least one &#39;&#39;&#39;&#39;flexible&#39;&#39;&#39;&#39; blade and an actuating means for moving a blade about a first axis. The blade (or blades) used employ: an edge member, a mounting means supporting the edge member so that it extends outwardly from the actuating means and so that it is capable of pivoting about a second axis extending outwardly from the first axis; a control batten pivotally mounted on the edge member adjacent to the actuating means so as to extend from the rear of the edge member and so as to be capable of pivoting relative to the edge member; and a triangular, flexible blade member having one of its sides attached to the edge member and another of its sides attached to the control batten. A control means is employed for controlling the angle of the control batten relative to the actuating means of the edge member.

United States Patent [191 Hill, deceased PROPULSION DEVICE HAVING AT LEAST ONE FLEXIBLE BLADE [76] Inventor: Arthur D. Hill, deceased, late of 459 E. 18th St., Costa Mesa, Calif. 92627 by Ann M. Hill, administratrix 221 Filed: Oct. 26, 1972 21 App]. No.: 300,984

[52] US. Cl. 416/132, 416/240 [51] Int. Cl. B64c 11/32 [58] Field of Search 416/132, 240, 157

[56] References Cited UNITED STATES PATENTS 954,992 4/1910 416/132 1,417,000- 5/1922 416/132 2,385,028 /1945 416/240 X 3,227,221 1/1966 416/132X 3,597,108 8/1971 416/240 X 2,377,386 6/1945 Stalker 416/157 X FORElGN PATENTS OR APPLICATIONS 532,399 11/1921 France 416/240 [.1 3,806,277 [451 Apr. 23, 1974 588,997 12/1933 Germany 416/240 Primary Examiner-Everette A. Powell, Jr.

[5 7] ABSTRACT A propulsion device is disclosed which uses at least one flexible blade and an actuating means for moving a blade about a first axis. The blade (or blades) used employ: an edge member, a mounting means supporting the edge member so that it extends outwardly from the actuating means and so that it is capable of pivoting about a second axis extending outwardly from the first axis; a control batten pivotally mounted on the edge member adjacent to the actuating means so as to extend from the rear of the edge member and so as to be capable of pivoting relative to the edge member; and a triangular, flexible blade member having one of its sides attached to the edge member and another of its sides attached to the control batten. A control means is employed for controlling the angle of the control batten relative to the actuating means of the edge member.

4 Claims, 4 Drawing Figures BACKGROUND OF THE INVENTION The subject matter set forth in this specification relates broadly to bladed type propulsion devices. Perhaps the earliest of such propulsion devices were structures as now may be referred to as paddles or oars. At the present time, however, the vast majority of such bladed propulsion devices are referred to as propellers. These devices utilize rotating propeller shafts which carry a plurality of symmetrically located blades. These blades bite or cut into a fluid such as air or water as the shaft is rotated. Such propellers arecommonly used on aircraft, boats and the like.

As constructed at the present time practically all bladed type propulsion devices utilize rigid blades. Frequently means are used with the more complex of these devices such as aircraft propellers to adjust the angles at which the blades are located relative to a propeller shaft so as to alter performance characteristics in accordance with conditions of operation. A great deal of study has gone into this type of thing. Further,.a great deal of work has been devoted to the precise manner in which the blades should be formed for various specific applications. This work with rigid type blades has undoubtedly resulted in propellers and related propulsion devices which are highly utilitarian and which are relatively effective. As the art pertaining to propulsion devices has developed it has apparently overlooked certain little known developments pertaining to the use of flexible blades in certain types of propulsion devices. The May 1939 issue of Popular Mechanics Magazine (Volume 71, No. 5) published by Popular Mechanics Corp, Chicago, Illinois on page 656 and the October 1939 issue of Popular Science Magazine, (Volume 135, No. 4) published by Popular Science Publishing Co., Inc., New York, NY. on page 103 both disclose so-called fishtail drive propulsion devices employing flexible blades used as propellers, skulling type mechanisms and the like. 7

Although propulsion devices are set forth in these publications were and are useable in achieving comparatively efficient propulsion under various specific conditions they have not been widely utilized or adopted. It is understood that the reasons for this pertain to the fact that'they are primarily effective only under specific conditions of use. Thus, for example, it is understood that one of the propulsion devices disclosed in these publications can be used by a man to propel a canoe through still water at 10mph. or better, but that this device was not desirably effective when used in other than still water or when actuated in other manners.

SUMMARY OF THE INVENTION A broadobjective of the present invention is to provide new and improved flexible blade propulsion devices which overcome various limitations of prior flexible blade propulsion devices as indicated in the precede ing discussion. From a consideration of the preceding it will be apparent that the invention is intended to provide propulsion devices which are effective under a wide variety of conditions of use, and which do not only provide effective performance under limted circumstances or conditions of use. The invention is primarily directed towards providing effective propulsion devices employing flexible blades which are intended to be used as propellers in small airplanes, small boats,

and the like, but is also concerned with other known types of blade carrying propulsion devices.

Another objective of the invention is to provide effective, economically desirable propellers. Further objectives of the invention are to provide propulsion devices utilizing flexible blades: which may be easily and conveniently manufactured; which are capable of providing prolonged reliable performance; and which may be easily and conveniently adjusted as they are used so as to operate as efficiently as reasonably possible under various specific use conditions.

In accordance with this-invention these and various related objectives of it are achieved by providing in a propulsion device having at least one blade and an actuating means for moving said blade relative to a first axis the improvement which comprises: the blade being formed so as to include an elongated edge member, mounting meansfor supporting one end of the edge member on the actuating means so that the edge member extends outwardly from the actuating means and is capable of pivoting about a second axis extending outwardly from the first axis, a control batten pivotally mounted on the edge member adjacent to the actuating means so as toextend from the rear of the edge member and so as to be capable of pivoting relative to the edge member, and a generally triangular, flexible blade member having one of its sides connected to the edge member. and another to the control batten.

Within a propulsion device of the invention control means are provided for controlling the angle of the control batten relative to the actuating means and the edge member during the use of the propulsion device. Preferably the blade also includes a plurality of battens extending across the flexible member from adjacent to the juncture of the control batten and the edge member in such a manner that'these battens diverge from one another as they extend away from this juncture. Preferably such a propulsion device is a propeller employing a plurality of these blades. Such a propulsion device may, however, be another known type of propulsion structure.

BRIEF DESCRIPTION OF THE DRAWING with and forming a part of this device;

FIG. 3 is a side elevational view taken from the righthand side of FIG. 1 showing a blade of the illustrated propeller at rest; and

FIG. 4 is a view similar to FIG. 3 showing the blade of the propeller substantially as it would appear during use. I

The accompanying drawing is primarily intended for use in explaining the intangible concepts of the present invention in connection with a specific presently preferred structure constructed in accordance with these concepts. These concepts are set forth and defined in the appended claims forming a part of this disclosure. It will be recognized that they can be embodied within various different types of propulsion devices in various different manners through the exercise of routine engineering skill on the basis of the disclosure embodied in this specification.

DETAILED DESCRIPTION In the drawing there is shown a propeller in accordance with this invention which is primarily intended to be utilized in propelling a small model type airplane. This propeller 10 employs as an actuating means a hollow shaft 12 which is adapted to be rotated in accordance with conventional practice. A small cap 14 is preferably located upon the end of the shaft 12 so as to deflect air outwardly from it during the use of this propeller 10. The propeller .10 utilizes two symmetrically arranged blades 16 as shown. It is to be understood that greater numbers of blades 16 can be employed if desired in this propeller 10. If such greater numbers are used these blades 16 should be symetrically located with respect to one another.

Each of the blades 16 has an elongated, planer edge member of an imporous, rigid preferably lightweight material. Each edge member l8 includes first and second ends 20 and 22,,respectively, connected by front and rear edges 24 and 26, respectively. Preferably each edge member 18 is slightly curved as shown. As a general rule, satisfactory results are achieved if the edge members 18 are of a flat configuration, but they can, however, be curved to a limited extent in much the manner in which conventional propeller blades are curved. They should not, however, be curved to the extent of conventional propeller blades. Each of these edge members 18 should preferably have a surface area corresponding to the surface area of from about to about 30 percent of the surface area of the entire blade 16 upon which it is located. It is considered that most efficient results are achieved when a blade 16 is constructed so as to have an area within this range.

Each of the blades 16 carries on its first end 22 a short shaft 28 which fits within a bearing 30 within the shaft 12. Heads 32 are provided on these shafts 28 so as to retain the blades 16 in such a manner that they can rotate about axes which are transverse to the axis of the shaft 12 during the use of the propeller 10. Each of the blades 16 includes a flat washer 34 located about a shaft 28 between the shaft 12 and the first end 20. These washers 34 are free to rotate about the shafts 28. They are rigidly secured to control battens 36 extending generally along the shaft 12 away from the edge member 18.

Each of the blades 16 includes a flexible blade member 38 of a generally triangular configuration which extends so that one of its sides is attached to the rear edge 26 of an edge member 18 between the ends and 22 of this edge member 18 and so that another of its sides is attached to a control batten 36 along the entire length of this batten 36. The blade members 38 used may be formed of a fabric-type material such as a silk or similar fabric. If such a fabric is used it should be treated so as to be substantially imporous in character. It is preferred to form the blade members 38 out of an imporous, flexible polymer material such as a polyethylene terephthalic film which as been stretched so as to develop its physical properties. Films of such material are desirable for use as the blade member 38 because of their lightness, their flexibility and their imporous character.

Each of the blade members 38 preferably carries a plurality of battens 44 roughly corresponding to the battens in a common sail. Although these battens 40 may be board or rod-type structures located in pockets in the blade members 38, it is considered preferable to form then as wire-like rods of a comparatively stiff material such as a known polyester composition. Battens 40 of this character can beused by being sealed through the application of heat or an adhesive directly to a blade member 38. Such battens 40 should be as light as possible, but should be sufficiently stiff so as to tend to minimize any bending of the blade members 38 along their lengths.

It will be noted that these battens 40 extend from adjacent to the first ends 20 of the edge members 18 in such a manner as to diverge outwardly from one another across the width of the blade members 38. These battens 40 are spaced from the junctures of the control battens 36 and the edge members 18 so that small portions of the blade members 38 adjacent to these junctures will act substantially as pivots. This avoids the necessity for using pivots with each of the battens 40. The battens 40 preferably extend completely across the blade members 38 to the rear edges 42 of these blade members.

In the propeller l0, flexible cables 44 are attached to the extremities of the control battens 36 remote from the edge members 18. These cables 44 extend through openings 46 in the shaft 12 past curved guides 48 to the rear of the shaft 12. Here, control means are provided for permitting rotation of the shaft 12 and for adjusting the effective lengths of these cables 44. In the structure shown such means include a mounting plate 50 secured to the ends of the cables 44. This plate 50 is carried by a conventional rotary joint 52. The extremity of this joint 52 remote from the cables 44 is secured to a conventional hydraulic cylinder 54 or a conventional mechanical equivalent which may be used in regulating theposition of the joint 52 and, hence, the effective lengths of the cables 44 between the shaft 12 and the control battens 36.

During the use of the propeller 10 it is rotated so that a blade 16 as shown in FIG; 4 moves in direction of the arrow in this figure. As the blade moves in this manner contact of the blade with the air within which it is moved will cause it to assume a configuration as indicated in FIG. 4, if the attached cable 44 is shortened as much as reasonably possible. As the blade 16 is moved and assumes this configuration, there will be flow along both of the surfacesof this blade. There will also be significant outward flow from the leading surface of the blade because of a build up of pressure along it.

During the flow in this manner it is considered that there is comparatively little vortex formation adjacent to the rear edge 42 because of minute vibrations within the blade member 38. It will' be recognized that such vortex formation is normally responsible for a lack of desired blade performance. If, during the operation of the propeller 10, there should be a tendency for such vortex formation, the cables 44 may be moved so as to allow the blades 16 to assume a position 'in which such vortex formation is minimized. During the operation of the blade 16 the various battens 40 serve to preserve I claim: 1. In a device for causing propulsion having atleast one blade and an actuating means for moving said blade relativeto a first axis, the improvement which comprises:

an elongated, rigid planar edge member having first and second ends and front and rear edges extending between said ends, t

mounting means for rotatably supporting said edge member connecting said first end of said edge member and said actuating means,

said mounting means serving to support said edge member so that it extends outwardly from said actuating means and so that it is capable of pivoting about a second axis extending outwardly from said first axis, a 1 i a control-batten pivotally mounted on said first end of said edgemember so as to extend from said rear edge of said edge member and so as to be capable of pivoting relative to said first end of said edge member, v

a flexible, generally triangular blade member, one side of which is attached to said edge member along the entire length of said rear edge of said edge member and one side of which is attached to said control batten along the length of said control batten,

said edge member and said blade member constituting said blade,

control means for controlling the angle of said control batten relative to said actuating means and said ing:

a plurality of battens extending across said flexible edge member during the use of said actuating means to move said blade, said control means connecting said control batten. and said actuating means,

said control means including a control cable extending from an extremity of said control batten remote from said edge member into the interior of said actuating means, and regulating means for regulating the length of said cable between the control batten and said actuating means during the utilization of said propulsion device,

said edge member having a surface area of from about 15 to about 30 percent of the entire surface area of said edge member and said blade member.

2. A propulsion device as claimed in claim I includmember to the edge of said flexible member extending between said second end of said edge member and said control batten from adjacent to said first end of said edge member, said battens diverging from one another away from said first end 7 of said edge member. 3. A propulsion device as claimed in claim l wherein:

said actuating means is a shaft capable of being rotate d about said first axis, and

there are a plurality of said blades located symmetrically about said axis.

4. A propulsion device as claimed in claim 3 including:

away from said corner. 

1. In a device for causing propulsion having at least one blade and an actuating means for moving said blade relative to a first axis, the improvement which comprises: an elongated, rigid planar edge member having first and second ends and front and reaR edges extending between said ends, mounting means for rotatably supporting said edge member connecting said first end of said edge member and said actuating means, said mounting means serving to support said edge member so that it extends outwardly from said actuating means and so that it is capable of pivoting about a second axis extending outwardly from said first axis, a control batten pivotally mounted on said first end of said edge member so as to extend from said rear edge of said edge member and so as to be capable of pivoting relative to said first end of said edge member, a flexible, generally triangular blade member, one side of which is attached to said edge member along the entire length of said rear edge of said edge member and one side of which is attached to said control batten along the length of said control batten, said edge member and said blade member constituting said blade, control means for controlling the angle of said control batten relative to said actuating means and said edge member during the use of said actuating means to move said blade, said control means connecting said control batten and said actuating means, said control means including a control cable extending from an extremity of said control batten remote from said edge member into the interior of said actuating means, and regulating means for regulating the length of said cable between the control batten and said actuating means during the utilization of said propulsion device, said edge member having a surface area of from about 15 to about 30 percent of the entire surface area of said edge member and said blade member.
 2. A propulsion device as claimed in claim 1 including: a plurality of battens extending across said flexible member to the edge of said flexible member extending between said second end of said edge member and said control batten from adjacent to said first end of said edge member, said battens diverging from one another away from said first end of said edge member.
 3. A propulsion device as claimed in claim 1 wherein: said actuating means is a shaft capable of being rotated about said first axis, and there are a plurality of said blades located symmetrically about said axis.
 4. A propulsion device as claimed in claim 3 including: a plurality of battens located on the blade member of each of said blades, the battens on each of said blade members extending from adjacent to the corner of said blade member between the control batten and said edge member to the edge of said blade member remote from said corner, said battens diverging from one another away from said corner. 